Quantum-Enhanced Sensing Enabled by Scrambling-Induced Genuine Multipartite Entanglement
Guantian Hu, Wenxuan Zhang, Zhihua Chen, Liuzhu Zhong, Jingchao Zhao, Chilong Liu, Zixing Liu, Yue Xu, Yongchang Lin, Yougui Ri, Guixu Xie, Mingze Liu, Haolan Yuan, Yuxuan Zhou, Yu Zhang, Chang-Kang Hu, Song Liu, Dian Tan, Dapeng Yu
Abstract
Quantum sensing leverages quantum resources to surpass the standard quantum limit, yet many existing protocols rely on the preparation of complex entangled states and Hamiltonian engineering, posing challenges for universality and scalability. Here, we report an experimental realization of a universal protocol, known as Butterfly Metrology, proposed in [arXiv:2411.12794], demonstrating a scrambling-based approach for quantum-enhanced sensing on a superconducting quantum processor. By exploiting many-body information scrambling, we observe quantum-enhanced sensitivity to an encoded phase beyond the standard quantum limit, with a scaling consistent with a factor-of-two of the Heisenberg limit for system sizes of up to 10 qubits. Importantly, we experimentally establish a connection between the enhanced sensitivity and the dynamics of the out-of-time-order correlator (OTOC), and show that the buildup of scrambling-induced genuine multipartite entanglement underlies the observed sensitivity enhancement. Our results demonstrate a scalable and practical approach for quantum-enhanced sensing in interacting many-body quantum systems.